As this type of method, for example, there has been suggested a method of reading address information recorded on an optical disc and obtaining information about the number of layers on a recording surface of the optical disc on the basis of the read address information in cases where the optical disc is inserted to an optical disc apparatus (refer to patent documents 1). Alternatively, there has been suggested a method of detecting S-shaped waveforms on the basis of electrical signals according to reflected light from the optical disc and judging or determining the number of layers of the optical disc on the basis of the detected S-shaped waveforms (refer to patent document 2).